Linux

How to verify that SSL for IMAP/SMTP works and a proper SSL certificate is in use

Credit Robert Asibekov IMAP via SSL using port 993 connect to a mail server using openssl: ...

Get Numeric File/Directory Permissions

Run the following command as root on a file/directory of your choice: stat -c %a /etc/hosts ...

Mount SMB Share in fstab Ubuntu

Username/Password in connect string Edit /etc/fstab: vi /etc/fstab Enter the following: ...

Find out what's taking up all the space in your linux install

Example for / partition: du -h / | grep '[0-9\.]\+G'

Extract Certificate Information with OpenSSL

Fetch the X.509 Public Key Certificate File openssl s_client -connect google.com:443 -showcerts ...

Run fstrim manually

fstrim / -v